Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754712AbaDKSDa (ORCPT ); Fri, 11 Apr 2014 14:03:30 -0400 Received: from terminus.zytor.com ([198.137.202.10]:45877 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753288AbaDKSD3 (ORCPT ); Fri, 11 Apr 2014 14:03:29 -0400 Message-ID: <53482E61.8050606@zytor.com> Date: Fri, 11 Apr 2014 11:03:13 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: =?ISO-8859-1?Q?Thomas_B=E4chler?= , Matt Fleming CC: Thomas Gleixner , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] efi: Clarify Kconfig help for EFI_MIXED References: <1397239154-30121-1-git-send-email-thomas@archlinux.org> In-Reply-To: <1397239154-30121-1-git-send-email-thomas@archlinux.org> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/11/2014 10:59 AM, Thomas B?chler wrote: > EFI stub support is only missing for a 64 bit kernel on 32-bit firmware, > on 64-bit kernels, EFI stub works as usual. > --- > > Matt, I don't know if this help was intentionally discouraging, > however, out of curiosity, I tested this with ovmf, and the > kernel boots fine on 64-bit firmware bit with EFI stub, and on > 32-bit firmware using efilinux. > > Documenting this properly is important for distribution kernels. > We would want to support this on Arch, but not if it means > introducing a regression for EFI stub users. > > arch/x86/Kconfig | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 5b8ec0f..2bbbbb9 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -1529,8 +1529,8 @@ config EFI_MIXED > mode. > > Note that it is not possible to boot a mixed-mode enabled > - kernel via the EFI boot stub - a bootloader that supports > - the EFI handover protocol must be used. > + kernel via the EFI boot stub on 32-bit firmware - a bootloader > + that supports the EFI handover protocol must be used. > > If unsure, say N. > Right, it is really that it is not possible to boot a mixed-mode kernel on its non-native firmware using the stub, since the stub itself can only be one way or the other. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/